The invention relates to an annular seal arrangement for producing a seal between interfitting parts and more particularly for interfitting parts which are able to be moved in relation to each other, preferably for the sealing of the valve piston of a multi-way valve in relation to the housing, comprising an elastically resilient inner ring placed in an ring-receiving recess and in front of which adjacent to the opening of the radially directed recess there is a coaxially arranged outer ring functioning as a more particularly loose sealing element. The invention furthermore is with respect to a valve fitted with such a sealing arrangement, which has a valve housing with an elongated piston receiving means, in which a plunger-like valve piston is arranged in an axially moving manner and into which on the periphery a plurality of valve ducts open.
A seal arrangement of this type has already been proposed, see for instance the Swiss patent 600,202. In this case the ring-receiving recess is a component of one of the two parts which are able to move in relation to each other and into which it is machined as a radial annular groove. This impedes assembly of the two rings, for which a substantial radial deformation is necessary. In this respect the rings may be damaged, something conducive to leaks in later use. There has admittedly already be a suggestion to make at least the outer ring with a slot as a remedy. In this case there are however leakage problems at the slot. Automated assembly of the seal arrangement is quite impossible.
A valve fitted with the seal arrangement in accordance with the said Swiss patent 600,202 is very complex to produce, is prone to cause sealing problems and is comparatively expensive.